bcrypt warnings inside of Docker - node.js

Question

Is there some solution to get rid of this warning? Console displays it during the Docker image creating. There are a lot of topics all over the internet and no working solution. Since bcrypt js lib creators think that it's fine to not fixing it for years maybe it's possible to import something manually or anything like that.
Node.js v12
bcrypt v3
Docker v19
> bcrypt#3.0.6 install /usr/src/app/node_modules/bcrypt
> node-pre-gyp install --fallback-to-build
node-pre-gyp WARN Using request for node-pre-gyp https download
make: Entering directory '/usr/src/app/node_modules/bcrypt/build'
CXX(target) Release/obj.target/bcrypt_lib/src/blowfish.o
CXX(target) Release/obj.target/bcrypt_lib/src/bcrypt.o
CXX(target) Release/obj.target/bcrypt_lib/src/bcrypt_node.o
In file included from ../src/bcrypt_node.cc:1:
../../nan/nan.h: In function 'void Nan::AsyncQueueWorker(Nan::AsyncWorker*)':
../../nan/nan.h:2232:62: warning: cast between incompatible function types from 'void (*)(uv_work_t*)' {aka 'void (*)(uv_work_s*)'} to 'uv_after_work_cb' {aka 'void (*)(uv_work_s*, int)'} [-Wcast-function-type]
, reinterpret_cast<uv_after_work_cb>(AsyncExecuteComplete)
^
In file included from ../../nan/nan.h:53,
from ../src/bcrypt_node.cc:1:
../src/bcrypt_node.cc: At global scope:
/root/.node-gyp/12.4.0/include/node/node.h:556:43: warning: cast between incompatible function types from 'void (*)(Nan::ADDON_REGISTER_FUNCTION_ARGS_TYPE)' {aka 'void (*)(v8::Local<v8::Object>)'} to 'node::addon_register_func' {aka 'void (*)(v8::Local<v8::Object>, v8::Local<v8::Value>, void*)'} [-Wcast-function-type]
(node::addon_register_func) (regfunc), \
^
/root/.node-gyp/12.4.0/include/node/node.h:590:3: note: in expansion of macro 'NODE_MODULE_X'
NODE_MODULE_X(modname, regfunc, NULL, 0) // NOLINT (readability/null_usage)
^~~~~~~~~~~~~
../src/bcrypt_node.cc:378:1: note: in expansion of macro 'NODE_MODULE'
NODE_MODULE(bcrypt_lib, init);
^~~~~~~~~~~
In file included from /root/.node-gyp/12.4.0/include/node/node.h:63,
from ../../nan/nan.h:53,
from ../src/bcrypt_node.cc:1:
/root/.node-gyp/12.4.0/include/node/v8.h: In instantiation of 'void v8::PersistentBase<T>::SetWeak(P*, typename v8::WeakCallbackInfo<P>::Callback, v8::WeakCallbackType) [with P = node::ObjectWrap; T = v8::Object; typename v8::WeakCallbackInfo<P>::Callback = void (*)(const v8::WeakCallbackInfo<node::ObjectWrap>&)]':
/root/.node-gyp/12.4.0/include/node/node_object_wrap.h:84:78: required from here
/root/.node-gyp/12.4.0/include/node/v8.h:9817:16: warning: cast between incompatible function types from 'v8::WeakCallbackInfo<node::ObjectWrap>::Callback' {aka 'void (*)(const v8::WeakCallbackInfo<node::ObjectWrap>&)'} to 'Callback' {aka 'void (*)(const v8::WeakCallbackInfo<void>&)'} [-Wcast-function-type]
reinterpret_cast<Callback>(callback), type);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/root/.node-gyp/12.4.0/include/node/v8.h: In instantiation of 'void v8::PersistentBase<T>::SetWeak(P*, typename v8::WeakCallbackInfo<P>::Callback, v8::WeakCallbackType) [with P = Nan::ObjectWrap; T = v8::Object; typename v8::WeakCallbackInfo<P>::Callback = void (*)(const v8::WeakCallbackInfo<Nan::ObjectWrap>&)]':
../../nan/nan_object_wrap.h:65:61: required from here
/root/.node-gyp/12.4.0/include/node/v8.h:9817:16: warning: cast between incompatible function types from 'v8::WeakCallbackInfo<Nan::ObjectWrap>::Callback' {aka 'void (*)(const v8::WeakCallbackInfo<Nan::ObjectWrap>&)'} to 'Callback' {aka 'void (*)(const v8::WeakCallbackInfo<void>&)'} [-Wcast-function-type]```

Answer 1

the warning is there for a reason, if you want to hide it, you have few choices
submit a fix to upstream to actually fix the code to remove the warning
hide it by submitting a fix to upstream and add -Wno-cast-function-type to gcc. it's up to maintainer to accept it.
submit a fix to upstream to add prebuilt binary for node 12 so that you won't have to compile every time (hence it won't trigger gcc to build). right now looks like only windows have prebuilt binary for node 12 (search for v72-linux)
https://github.com/kelektiv/node.bcrypt.js/releases/tag/v3.0.6

Answer 2

Are you able to use bycryptjs to avoid this issue?
The bycrypt entirely depends on the node version. Or you have to choose the suitable version of bycrypt or downgrade the version of bycrypt